Prosthetic Heart Valve Having Tubular Seal

ABSTRACT

A prosthetic heart valve includes a plurality of leaflets and an expandable member including one or more braided wires with a first set of wire segments extended helically in a first direction and a second set of wire segments extended helically in a second direction such that each wire segment of the first set intersects a plurality of wire segments from the second set at a plurality of intersection points. The one or more braided wires can have crowns where the wire segments of the first set connect to wire segments of the second set. The heart valve can include a tubular seal secured to the plurality of leaflets and to the expandable member by a plurality of sutures. The sutures can include cross stitches formed around both a wire segment of the first set and a wire segment of the second set at one of the intersection points.

RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application No.62/111,472, file Feb. 3, 2015.

FIELD

This document provides prosthetic heart valves having a tubular seal.

BACKGROUND

The human heart contains four valves: a tricuspid valve, a pulmonicvalve, a mitral valve and an aortic valve. The main purpose of thevalves is to maintain unimpeded forward flow through the heart and intothe major blood vessels connected to the heart, for example, thepulmonary artery and the aorta. As a result of a number of diseaseprocesses, both acquired and congenital, any one of the four heartvalves may malfunction and result in either stenosis (impeded forwardflow) and/or backward flow (regurgitation). Either process burdens theheart and may lead to serious problems, for example, heart failure.Various procedures for fixing or replacing defective heart valves areknown in the art. In some cases, artificial heart valves can beimplanted in the heart of a patient to replace a diseased or damagedheart valve with a prosthetic equivalent.

Prosthetic heart valves can have a variety of designs. Two major typesof prosthetic heart valves include mechanical heart valves andbioprosthetic heart valves. Mechanical heart valves can be made ofsynthetic materials, such as plastics or metals, while bioprostheticheart valves can be made of biologic tissue mounted on a fabric coveredplastic or metal frame. Bioprosthetic heart valves can include animaltissue, such as porcine or bovine tissue, that has been chemicallytreated to make the valve suitable for implantation in a human.Bioprosthetic valves do not generally require a patient to undergoanticoagulant therapy, which is typically required when using mechanicalvalves. As such, there is a need to further improve the design ofbioprosthetic valves to retain its functionality during the life of thepatient and minimize stenosis and regurgitation.

SUMMARY

Prosthetic heart valves provided herein can have a structure adapted toretain functionality during the life of the patient and minimizestenosis and/or regurgitation by having an improved connection betweendifferent parts of a prosthetic heart valve.

In Example 1, a prosthetic heart valve includes an expandable membercomprising one or more braided wires, the one or more braided wirescomprising a first set of wire segments extended helically in a firstdirection and a second set of wire segments extended helically in asecond direction such that each wire segment of the first set intersectsa plurality of wire segments from the second set at a plurality ofintersection points, wherein the one or more braided wires have crownswhere the wire segments of the first set connect to wire segments of thesecond set. The prosthetic heart valve can additionally include aplurality of leaflets being secured within the expandable member and atubular seal comprising an elastomeric material, the tubular seal havingan inflow edge being secured to bottom inflow edges of the plurality ofleaflets and to the expandable member by a plurality of sutures,characterized by the sutures comprising cross stitches formed aroundboth a wire segment of the first set and a wire segment of the secondset at one of the intersection points.

In Example 2, the prosthetic heart valve of Example 1, wherein eachcross stitch is an independently tied off stitch unconnected to othercross stitches.

In Example 3, the prosthetic heart valve of either Example 1 or Example2, wherein each cross stitch is attached at an intersection pointimmediately adjacent a crown at an inflow side of the expandable member.

In Example 4, the prosthetic heart valve of any of Examples 1-3, whereinthe plurality of leaflets are secured together along side edges thereof.

In Example 5, the prosthetic heart valve of Example 4, wherein theplurality of leaflets each comprise two sleeve portions, wherein thesleeve portions are secured to the expandable member by a plurality ofanchor elements.

In Example 6, the prosthetic heart valve of any of Examples 1-5, whereinthe tubular seal comprises a plurality of non-elastic fibers retainedwithin a matrix of the elastomeric material, the non-elastic fibersbeing arranged to allow the tubular seal to stretch in an axial or aradial direction.

In Example 7, the prosthetic heart valve of Example 6, wherein thenon-elastic fibers are part of a fabric.

In Example 8, the prosthetic heart valve of Example 7, wherein thefabric is a woven fabric.

In Example 9, the prosthetic heart valve of Example 8, wherein the wovenfabric comprises fibers in a warp direction and fibers in a waftdirection, wherein the fibers in both the warp direction and the waftdirection are angled with respect to a central axis of the tubular seal.

In Example 10, the prosthetic heart valve of Example 9, wherein thefibers in both the warp direction and the waft direct are angled at anangle between 5 degrees and 70 degrees with respect to the central axisof the tubular seal.

In Example 11, the prosthetic heart valve of Examples 6-10, wherein thenon-elastic fibers are uniformly dispersed throughout the elastomericpolymer matrix.

In Example 12, the prosthetic heart valve of Example 11, wherein thetubular seal has a substantially uniform thickness.

In Example 13, the prosthetic heart valve of any of Examples 1-10,wherein the tubular seal comprises an outflow end region and an inflowend region, the inflow end region being a portion of the tubular sealcomprising a fabric within a matrix of the elastomeric matrix, whereinthe fabric has a non-linear edge defining an interface between theinflow end region and the outflow end region.

In Example 14, the prosthetic heart valve of Example 13, wherein thenon-linear edge of the fabric has a sinusoidal or scalloped shape.

In Example 15, the prosthetic heart valve of any of Example 1-14,wherein the plurality of leaflets are secured to the tubular seal by acontinuous circumferential running stitch.

In Example 16, a prosthetic heart valve can include an expandable membercomprising one or more braided wires, the one or more braided wirescomprising a first set of wire segments extended helically in a firstdirection and a second set of wire segments extended helically in asecond direction such that each wire segment of the first set intersectsa plurality of wire segments from the second set at a plurality ofintersection points, wherein the one or more braided wires have crownswhere the wire segments of the first set connect to wire segments of thesecond set. The prosthetic heart valve can additionally include aplurality of leaflets being secured within the expandable member and atubular seal comprising an elastomeric material, the tubular seal havingan inflow edge being secured to bottom inflow edges of the plurality ofleaflets and to the expandable member by a plurality of sutures,characterized by the sutures comprising cross stitches formed aroundboth a wire segment of the first set and a wire segment of the secondset at one of the intersection points.

In Example 17, the prosthetic heart valve of Example 16, wherein eachcross stitch is an independently tied off stitch unconnected to othercross stitches.

In Example 18, the prosthetic heart valve of Example 16, wherein eachcross stitch is attached at an intersection point immediately adjacent acrown at an inflow side of the expandable member.

In Example 19, the prosthetic heart valve of Example 16, wherein theplurality of leaflets are secured together along side edges thereof.

In Example 20, the prosthetic heart valve of Example 19, wherein theplurality of leaflets each comprise two sleeve portions, wherein thesleeve portions are secured to the expandable member by a plurality ofanchor elements.

In Example 21, the prosthetic heart valve of Example 16, wherein thetubular seal comprises a plurality of non-elastic fibers retained withina matrix of the elastomeric material, the non-elastic fibers beingarranged to allow the tubular seal to stretch in an axial or a radialdirection.

In Example 22, the prosthetic heart valve of Example 21, wherein thenon-elastic fibers are part of a fabric.

In Example 23, the prosthetic heart valve of Example 22, wherein thefabric has a thickness ranging from about 40 to about 80 microns.

In Example 24, the prosthetic heart valve of Example 22, wherein thefabric is a woven fabric.

In Example 25, the prosthetic heart valve of Example 24, wherein thewoven fabric comprises fibers in a warp direction and fibers in a waftdirection, wherein the fibers in both the warp direction and the waftdirection are angled with respect to a central axis of the tubular seal.

In Example 26, the prosthetic heart valve of Example 25, wherein thefibers in both the warp direction and the waft direct are angled at anangle between 5 degrees and 70 degrees with respect to the central axisof the tubular seal.

In Example 27, the prosthetic heart valve of Example 22, wherein thefibers are made of polyester.

In Example 28, the prosthetic heart valve of Example 21, wherein thenon-elastic fibers are uniformly dispersed throughout the matrix.

In Example 29, the prosthetic heart valve of Example 16, wherein thetubular seal has a substantially uniform thickness.

In Example 30, a prosthetic heart valve includes an expandable membercomprising one or more braided wires, the one or more braided wirescomprising a first set of wire segments and a second set of wiresegments such that each wire segment of the first set intersects aplurality of wire segments from the second set at a plurality ofintersection points. The prosthetic heart valve can also include aplurality of leaflets secured within the expandable member and a tubularseal including an elastomeric material. The tubular seal can have aninflow edge being secured to bottom inflow edges of the plurality ofleaflets and to the expandable member by a plurality of sutures. Thesutures can include cross stitches formed around both a wire segment ofthe first set and a wire segment of the second set at one of theintersection points, wherein the tubular seal comprises an outflow endregion and an inflow end region. The inflow end region can be a portionof the tubular seal including a fabric within a matrix of an elastomericmatrix, wherein the fabric has a non-linear edge defining an interfacebetween the inflow end region and the outflow end region.

In Example 31, the prosthetic heart valve of Example 30, wherein thenon-linear edge of the fabric has a sinusoidal or scalloped shape.

In Example 32, the prosthetic heart valve of Example 30, wherein theplurality of leaflets are secured to the tubular seal by a continuouscircumferential running stitch.

In Example 33, the prosthetic heart valve of Example 30, wherein thefirst set of wire segments extends helically in a first direction and asecond set of wire segments extends helically in a second direction.

In Example 34, the prosthetic heart valve of Example 33, wherein the oneor more braided wires have crowns where the wire segments of the firstset connect to wire segments of the second set.

In Example 35, a method of making a tubular seal of a prosthetic heartvalve includes forming a tubular seal that includes a fabric within amatrix by dipping a mandrel with a first coating composition that has atleast one elastomeric polymer. The method can also include drying thefirst coating composition. The method can also include positioning thefabric on the mandrel and applying a second coating composition on themandrel. The second coating composition can be different than the firstcoating composition. The method can further include removing the tubularseal from the mandrel.

The details of one or more embodiments of the invention are set forth inthe accompanying drawings and the description below. Other features,objects, and advantages of the invention will be apparent from thedescription and drawings, and from the claims.

DESCRIPTION OF DRAWINGS

FIGS. 1A-1H illustrate an exemplary prosthetic heart valve and anexemplary deployment device provided herein. FIG. 1A is a perspectiveview of the heart valve connected to the deployment device. FIG. 1B is aside view of the exemplary prosthetic heart valve. FIGS. 1C-1Hillustrate how the exemplary heart valve provided herein can bedelivered by the deployment device.

FIGS. 2A-2C illustrates an exemplary leaflet, which can be used inprosthetic heart valves provided herein. FIG. 2A illustrates a roundednotch in a leaflet where a leaflet can be secured to an adjacentleaflet. FIGS. 2B and 2C illustrate a portion of an exemplary leafletfor prosthetic heart valves. FIG. 2B depicts the rounded notch in anarmpit of a leaflet. FIG. 2C depicts attachment elements in the armpitof the leaflet.

FIG. 3 illustrates another exemplary leaflet, which can be used inprosthetic heart valves provided herein. FIG. 3 depicts apertures in abody of the exemplary leaflet.

FIGS. 4A-4G illustrate how adjacent leaflets can be stitched together inprosthetic heart valves provided herein.

FIGS. 5A-5C illustrate a cross stich provided herein for connecting aseal to a braided stent in an exemplary prosthetic heart valve providedherein. FIG. 5A shows a front view of a seal having apertures and stitchpatterns used for securing the seal to the braided stent. FIG. 5Bdepicts a close up view of a cross stitch and a portion of acircumferential stitch used for securing the seal to the braided stent.FIG. 5C depicts a cross-sectional view showing the cross stitch and aportion of the circumferential stitch.

FIG. 6 depicts an apparatus that can be used to form a tubular sealprovided herein.

FIGS. 7A-7E depict exemplary tubular seals having a fabric positionedwithin a matrix that can be used in a prosthetic heart valve providedherein.

Like reference symbols in the various drawings indicate like elements.

DETAILED DESCRIPTION

Prosthetic heart valves provided herein can include a braided stentexpandable member secured to a tubular seal using a plurality of crossstitches at a plurality of intersection points of wires of the braidedstent. Stitching at intersection points (e.g., intersection pointsimmediately adjacent to inflow crowns) as opposed to at inflow crownscan increase the strength of the attachment while also allowing forimproved load transfer to the braided stent. Each stitch, which isdescribed in further detail below, can be formed by passing two stitchesof suture in orthogonal directions over the wire intersections, passingthrough the fabric strip in four locations. Each cross stitch can beindividual knotted. In some cases, the cross stitches do not passthrough any of the leaflets. The cross stitch can be repeated at manyintersections circumferentially around an inflow end of a prostheticheart valve provided herein until the entire length of the tubular sealis securely attached.

FIGS. 1A and 1B illustrate an exemplary prosthetic heart valve 100provided herein. FIGS. 1C-1H depict how prosthetic heart valve 100 isdeployed. FIG. 1A is a perspective view of prosthetic heart valve 100connected to a deployment device 190. FIG. 1B is a side view ofprosthetic heart valve 100. As shown, prosthetic heart valve 100includes an expandable member 110, three leaflets 200, three anchorelements 120 that secure sleeve portions 216 of leaflets 200 toexpandable member 110, and a tubular seal 130 secured around a bloodinflow end of prosthetic heart valve 100. Anchor elements 120 caninclude post leg compression elements 122 and clamping supportstructures 126 adapted to provide support along opposite sides of thesleeve portions 216. Expandable member 110 in FIGS. 1A-1D is a braidedstent, which is adapted to transition between a restricted state havinga smaller diameter and an expanded state having a larger diameter.Expandable member 110 can be self-expanding, mechanically expanded, or acombination thereof.

FIGS. 1C-1H depict how an exemplary heart valve delivery system candeliver the prosthetic heart valve provided herein. As shown in FIGS.1C-1H, prosthetic heart valve 100 can be deployed using a heart valvedelivery system 180. System 180 can include a sheath 182 for retainingthe prosthetic heart valve 100 with the expandable member 110 in arestricted state. Within sheath 182, anchor elements 120 (FIGS. 1A and1B) can be connected to pushing prongs 192 and a pull line 194 can beconnected to a nose cap 196, or end cap, which is positioned at the endof the sheath 182. As shown in FIG. 1A, the pull line 194 can extendthrough expandable member 110 and through the valve opening between theleaflets 200. As shown by FIGS. 1D-1H, once a distal end of sheath 182is delivered through the circulatory system to an appropriate location(e.g., within the heart), prosthetic heart valve 100 can be deployed. Byadvancing pushing prongs 192 and pull line 194 relative to sheath 182,prosthetic heart valve 100 can be pushed out of the sheath 182. In somecases, expandable member 110 can self-expand upon exiting sheath 182. Insome cases, expandable member 110 can self-expand to a firstintermediate diameter, and system 180 can mechanically expand expandablemember 110 to a larger deployment diameter. For example, anchor elements120 can include a locking mechanism to clip a portion of expandablemember when the expandable member 110 is expanded to a predeterminedlocking diameter. In some cases, system 180 can mechanically expandexpandable member 110 to a predetermined locking diameter. In somecases, system 180 can compress expandable member 110 between pushingprongs 192 and nose cap 196 by moving pull line 194 relative to pushingprongs 192. The predetermined locking diameter can be adapted to set thediameter of the prosthetic heart valve 100 during implantation. Afterprosthetic heart valve 100 is set, system 180 can move pull line 194 andnose cap 196 relative to pushing prongs 192 to move the end cap throughthe opening between leaflets 200 in prosthetic heart valve 100. Pushingprongs 192 can then be retracted from anchor elements 120 and retractedinto sheath 182. In some cases, pushing prongs 192 can include a shapemember material adapted to help radially expand expandable member 110 asthe expandable member 110 exits sheath 182. A control handle 188 can beused to control the relative movements of sheath 182, pushing prongs192, and pull wire 194. Prosthetic heart valves provided herein can beadapted to mitigate damage that might otherwise occur to valves duringdelivery and implantation.

In some cases, one or more radiopaque markers can be secured toprosthetic heart valves provided herein. As shown in FIGS. 1A and 1B,expandable member 110 includes a radiopaque marker 112. Any suitableradiopaque material (such as platinum, palladium, gold, tantalum, oralloys thereof) can be used as the radiopaque material in radiopaquemarker 112. One or more radiopaque markers can be used with an imagingsystem to help a physician ensure that a valve is set in an appropriatelocation. In some cases, prosthetic heart valves provided herein includeat least three radiopaque markers.

As shown in FIG. 1A, prosthetic heart valve 100 can include a pluralityof leaflets 200. In some cases, as shown, prosthetic heart valve 100includes three leaflets 200. In some cases, prosthetic heart valvesprovided herein can have any suitable number of leaflets, such as two,three, four, five, or more leaflets. In some cases, leaflets 200 aresecured to one another. In some cases, leaflets 200 can be secured toone another via a plurality of sutures. Leaflets 200 can be suturedalong side edges of a body portion of each leaflet. In some cases,prosthetic heart valves provide herein can include a single line ofsutures, which can be adapted to minimize leaks, minimize the width of aseam, and/or minimize the profile of a replacement heart valve duringpercutaneous insertion. In some cases, prosthetic heart valves provideherein can include multiple lines of sutures.

Expandable member 110 can have any suitable structure, arrangement, ormaterial. In some cases, expandable member 110 can include a braidedwire stent. For example, U.S. Publication Number 2005/0143809, titled,“Methods and Apparatus for Endovascularly Replacing a Heart Valve,” andfiled on Nov. 5, 2004, which is herein incorporated by reference for itsdisclosure of possible structures and materials for a braided wirestent, discloses a braided wire stent. In some cases, expandable member110 includes a shape memory material (e.g., a nickel-titanium alloy or acobalt-chromium alloy).

Referring to FIGS. 2A-2C, a leaflet 200 can include a body portion 214and sleeve portions 216. In some cases, the body portion 214 has abottom edge 222, a first side edge 226, a second side edge 228, and afree edge 224. Leaflet 200 further includes a front (i.e., the side thatblood flows toward), a back (i.e., the side that blood flows away from),a first side adjacent to the first side edge 226, and a second sideadjacent to the second side edge 228. In some cases, the front of theleaflet 200 has a different texture than the back. In some cases, forexample, the back of the leaflet may be prone to calcium build due toits cusp-shaped surface, therefore it can be beneficial to have atextured surface on the back of the leaflet to mitigate valvecalcification issues. In some cases, however, having the back with anon-textured surface can mitigate calcification issues. In some cases,the leaflet 200 is made from tissue obtained from an animal, e.g., a pigor a cow. In some cases, leaflet 200 is made from bovine pericardium.Leaflets 200 can also be made from a synthetic material. Leaflets 200can be assembled into a heart valve by aligning the opposite sideregions of at least two adjacent leaflets 200 and stitching the leaflets200 together along stitch line 246, as shown in FIG. 2C.

As shown in FIGS. 2A-2C, a prosthetic heart valve can include at leastone leaflet 200 having a body portion 214 and two opposite sleeveportions 216. The body portion 214 can be defined by two side edges 226,228 adjacent each sleeve portion 216. The at least one leaflet 200 candefine at least one notch 232, 234 between at least one of the two sideedges 226, 228 and the adjacent sleeve portion 216. In other words, eachnotch 232, 234 can be located along the side edges 228, 226 at alocation that is adjacent to the sleeve portions 216, at an armpit ofthe leaflet 200, as depicted in FIGS. 2A and 2B. In some cases, leaflet200 can define a notch 232, 234 generally along the side edges 228, 226.In some cases, a notch 232, 234 can be defined along the sleeve portion216. In some cases, multiple notches 232, 234 can be located along thesleeve portion 216 or one of the side edges 228, 226, and/or at thearmpit of the leaflet 200.

As shown in FIG. 2A and 2B, the body portion 214 of the leaflet can havea conical frustum shape defined by a bottom edge 222, the first sideedge 226, the second side edge 228, and a free edge 224. In some cases,other suitable shapes for the body portion can be contemplated, forexample, a generally square, rectangular, triangular or trapezoidalshaped body portion.

The sleeve portions, as shown in FIGS. 2A-2C, can extend outwardly fromthe body portion of the leaflet 200. Each sleeve portion may be angledaway from free edge of the body portion. Sleeve portions can begenerally rectangular-shaped extensions with lateral ends. In somecases, the sleeve portions can have rounded ends.

Still referring to FIGS. 2A-2C, notches 232, 234 can be generallyU-shaped. Other suitable notch shapes can include, but are not limitedto, a V-shaped, Z-shaped, rectangular-shaped and an oval-shaped notch.Notches can also have rounded edges to smooth the transition between anotch and the side edges 228, 226 of the leaflet 200. Notches 232, 234can have a length dimension that can range from about 0.02 inches toabout 0.20 inches (or from about 0.5 millimeters (mm) to about 4 mm).

Referring to FIG. 2C, notches 232, 234 can be shaped and sized toaccommodate attachment of post leg compression elements 122. Post legcompression elements 122 can be a part of anchor elements 120 (shown inFIGS. 1A and 1B) that compress and restrain sleeve portions 216 alongthe same line as the stitch line 246. A suture 258 can be used to applyan appropriate and consistent compressive force between the post legcompression elements 122 in order to prevent leakage through sleeveportions 216 of the leaflets 200. Sutures that pierce the body portion214 at or near the armpit of the leaflet, however, can pull, stretch andabrade the surrounding adjacent tissue, creating stress concentrationsat or near the armpit of the leaflet. Stress concentrators can result intears forming in the leaflet material. Using notches 232 and 234 andpost leg compression elements 122, however, can minimize potential heartvalve tearing caused by sutures at or near the armpit location. Notches232, 234 can be positioned proximate to the post leg compressionelements near the armpit of the leaflet, e.g., between at least one ofthe two side edges 226, 228 and the adjacent sleeve portion 216, tocreate enlarged openings that suture 258 can pass therethrough withoutpulling or stretching the adjacent tissue. Accordingly, a notchedleaflet 200 can improve valve opening capabilities and the reliabilityof prosthetic heart valves provided herein.

FIG. 3 illustrates another exemplary leaflet, which can be used inprosthetic heart valves provided herein. As shown in FIG. 3, leaflet 300can include a body portion 314 and at least two opposite sleeve portions316. The body portion 314 can be defined by at least two side edges 326,328 adjacent each sleeve portion 316. Leaflet 300 can define twoapertures 332 and 334. Each aperture 332, 334 can be positioned adjacentthe side edges 326, 328 and an adjacent sleeve portion 316. Eachaperture 332, 334 can be adapted to secure one leaflet to an adjacentleaflet.

In some cases, the body portion 314 has a bottom edge 322, a first sideedge 326, a second side edge 328, and a free edge 324. Leaflet 300further includes a front, a back, a first side adjacent to the firstside edge 326, and a second side adjacent to the second side edge 328.In some cases, the front of the leaflet 300 has a different texture thanthe back. In some cases, this occurs where the leaflet 300 is made frompig, cow, or other natural animal tissue. In some cases, leaflet 300 ismade from bovine pericardium. Leaflets 300 can also be made from asynthetic material. Leaflets 300 can be assembled into a heart valve byaligning the opposite side regions of at least two adjacent leaflets 300and stitching the leaflets 300 together along stitch line 246, as shownin FIG. 2C.

As shown in FIG. 3, leaflet 300 defines apertures 332 and 334 adjacentthe side edges 328, 326 and adjacent the sleeve portions 316. Apertures332 and 334 can be generally circular in shape. Other suitable apertureshapes can include, for example, a rectangular, an oval, a triangular,or a diamond shape. In some cases, apertures 332, 334 can have a lengthdimension or a diameter from about 0.02 inches to about 0.20 inches (orfrom about 0.5 mm to about 4 mm). In some cases, one or more apertures332, 334 can be located in the side edges 328, 326 and/or the sleeveportions 316 of the leaflet 300. In some cases, multiple apertures canbe located in a region that is adjacent to the side edges 328, 326 andthe sleeve portions 316.

Apertures 332, 334 in the leaflets 300 can allow one leaflet to besecured to an adjacent leaflet. Similar to the notches discussed above,apertures 332 and 334 can be shaped and sized to accommodate attachmentof post leg compression elements 122. Referring back to FIGS. 1A and 1B,post leg compression elements 122 can be a part of anchor elements 120that compress and restrain sleeve portions 216 along the same line asthe stitch line 246. A suture 258 can be used to apply an appropriateand consistent compressive force between the post leg compressionelements 122 in order to prevent leakage through sleeve portions 216 ofthe leaflets 200. As already discussed herein, sutures that pierce thebody portion 214 at or near the armpit of the leaflet can create stressconcentrations at or near the armpit of the leaflet that may result intearing. Apertures 332 and 334 and post leg compression elements 122,however, can minimize this potential tearing caused by sutures near thearmpit location. Apertures 332, 334 can be positioned proximate to thepost leg compression elements near the armpit location to createenlarged openings that suture 258 can pass therethrough without pullingor stretching the adjacent tissue. Accordingly, leaflets 300 used inprosthetic heart valves provided herein can improve the reliability ofprosthetic heart valves provided herein.

FIGS. 4A-4G depict how leaflets 200 can be connected (or jointed) withan improved stitch discussed herein. As shown, stitch 446 can be asingle continuous line stitch traveling along a stitch line in a forwarddirection and back in a reverse direction. In some cases, stitch 446 canrun along a leaflet from a bottom edge to a side edge of the leaflet(e.g., bottom edge 222 to side edge 226 of leaflet 200 in FIG. 2A-2B).In some cases, stitch 446 can run from a side edge to a notch of aleaflet (e.g., side edge 226 to notch 234 of leaflet 200 in FIG. 2A-2B).

As shown in FIGS. 4D-4G stitch 446 can include a plurality ofperpendicular loop segments 434 extending through an aperture in the twoleaflets, around outer side edges of the two attached leaflets, and backthrough the aperture. Stitch 446 can include a plurality of parallelsegments 436 extending between adjacent apertures along the stitch line.Stitch 446 can include two perpendicular loop segments 434 extendingthrough apertures formed in the stitch line. In some cases, a firstperpendicular loop segment 434 for a first aperture in the stitch lineis formed when the stitch is formed in the forward direction and asecond perpendicular loop segment 434 for the first aperture is formedin the reverse direction. In some cases, parallel segments 436 made in aforward direction alternate between opposite sides of the two leafletsbetween each aperture in the stitch line. In some cases, parallelsegments 436 made in a reverse direction are formed on an opposite sideof the two leaflets from parallel segments 436 made in a forwarddirection. In some cases, opposite parallel segments 436 made in theforward and reverse directions can provide a continuous compressiveforce along the entire length of the stitch line. Perpendicular loopsegments 434 can provide compressive force to reinforce a seal formedbetween the two leaflets along the stitch line.

Stitch 446 can include any appropriate number of perpendicular loopsegments formed through any appropriate number of apertures. As shown,stitch 446 includes six perpendicular loop segments formed through sixapertures (two perpendicular loop segments per aperture). In some cases,stitch 446 can include up to twelve perpendicular loop segments formedthrough six or more apertures. In some cases, a stitch connecting sideedge segments of leaflets can be formed using between 3 and 20 aperturesand include between 3 and 40 perpendicular loop segments. In some cases,apertures can be positioned from about 0.008 inches to about 0.4 inchesapart (about 0.2 mm to about 10 mm apart). In some cases, apertures canbe positioned from about 0.008 inches to about 0.4 inches (about 0.2 mmto about 10 mm) away from the side edges of the leaflets.

Stitch 446 can be formed in a process depicted in FIGS. 4A-4G As shownin FIG. 4A, a thread needle 410 can be passed through aligned leafletside edges 226 a and 226 b to create a first aperture at a location nearbottom edges 222, e.g., a location approximately 1 mm from the bottomedges 222. The leaflet side edges 226 a and 226 b can be retained in adesired configuration by clamping the leaflets between clamp sides 422and 424. Needle 410 pulls a leading end 431 of a thread 432 through thefirst aperture. As shown in FIG. 4B, needle 410 can then form a secondaperture adjacent to the first aperture along the stitch line (towardsthe leaflet sleeve portion) about 0.5 mm away from the first aperture topull leading end 431 of thread 432 through the second aperture to form afirst parallel segment. As shown in FIG. 4C, a perpendicular loopsegment 434 can be made by guiding needle 410 around the leaflet sideedges and re-enter the second aperture from a backside. Thread 432 canbe pulled through the second aperture until it sits firmly against theleaflet material (e.g., leaflet pericardium tissue). FIG. 4D shows asecond parallel segment, which can be made by pushing needle 410 throughleaflet tissue along the stitch line to form a third apertureapproximately 1 mm from the second aperture (towards the sleeve segmentsof the leaflet). As shown in FIG. 4E, a second perpendicular loopsegment 434 can be formed by again having needle 410 loop around theleaflet side edges and reenter the third aperture through the backside.This is repeated up to notch 234 to form a total of six parallelsegments 436 and six perpendicular loop segments 434 in a forwarddirection, as shown in FIG. 4F. The stitch pattern can then be repeatedin a reverse direction towards the bottom edges 222 of the leafletsthrough the previously formed apertures. Accordingly, each aperture caninclude two perpendicular loop segments 434 and parallel segments on theopposite sides can be formed from the parallel segments that werecreated in the forward direction, as shown in FIG. 4G The method andstitches depicted in FIGS. 4A-4G can be applicable to leaflets 200, 300discussed herein.

Stitch 446 and other stitches provided herein can improve thereliability of a seal formed along a stitch line, create fewer aperturesthrough the leaflets, and simplify the stitching operation. Having fewerapertures can help minimize the occurrence of blood leakage through theapertures. The single continuous line of stitch 446 using a single rowof apertures can minimize a width of a side edge portion needed to forma continuous seal along the side edges of the leaflets, thus providing areduced restricted profile for prosthetic heart valves provided herein.For example, U.S. Pat. No. 8,778,020 describes a variety of ways thatleaflets can be sutured together using combinations of whip stitches andrunning stitches, but these stitches require additional apertures andmultiple lines. Perpendicular loop segments 434 can stitch a pluralityof leaflets together, similar to the whip stitches discussed in U.S.Pat. No. 8,778,020. Parallel segments 436 can secure valve leaflets toone another, similar to the running stitches discussed in U.S. Pat. No.8,778,020. Although stitch 446 can provide an improved attachmentbetween side edges of leaflets in prosthetic heart valves providedherein, some embodiments of prosthetic heart valves provided herein canuse other stitch patterns, such as those described in U.S. Pat. No.8,778,020, which is hereby incorporated by reference.

Important characteristics of the thread can include, but are not limitedto, tensile strength, abrasion resistance and creep rupture resistancecharacteristics that allow the device to be delivered and implanted intoa human anatomy. The thread used for suturing together portions of theheart valve, e.g., sides edges of the leaflets, can be composed ofbiocompatible materials that include, but are not limited to,polyethylenes such as ultra high molecular weight polyethylene (UHMWPE),polyesters (PET), and combinations thereof.

Referring back to FIGS. 1A and 1B, prosthetic heart valve 100 caninclude a tubular seal 130. Tubular seal 130 can be secured to bottomedges 222 (FIG. 2A) of the body portion 214 of at least one leaflet 200by a circumferential running stitch 134 within prosthetic heart valve100. Tubular seal 130 can be secured to expandable tubular member 110 byfasteners 136 and extended around the outside of expandable tubularmember 110 to provide a seal that minimizes blood leakage around theleaflets 200 of an implanted prosthetic heart valve 100. The structureand materials of tubular seal 130 are discussed below in reference toFIGS. 6 and 7A-7E.

Referring to FIGS. 5A-5C, an improved tubular seal stitching pattern caninclude a cross stitch 132 between tubular seal 130 and expandablemember 110. FIGS. 5A-5C illustrate how the tubular seal 130 can besecured to the expandable member 110, e.g., a braided stent, by aplurality of cross stitches connecting the tubular seal 130 to a pair ofoverlapping wire members of the braided stent. As shown in FIGS. 1A, 1Band 5A-5C, expandable member 110 can be a braided stent including one ormore wires having a first set of segments 114 extending helically in afirst direction and a second set of segments 116 extending helically ina second direction such that the first set of segments 114 cross thesecond set of segments 116 at intersection points 118. As shown, one ormore wires can have inflow crowns 115 at an end of the braided stentwhere the wires transition from first segments 114 to second segments116. In some cases, cross stitches 132 secure tubular seal 130 at anintersection 118 to two crossing segments 114, 116 of the braided stent.A separate circumferential running stitch 134 can be inserted intopreformed apertures 133 to secure the adaptive seal to bottom edges 222of leaflets 200 shown in FIGS. 2A and 2C. Cross-stitches around theintersections 118 can increase the strength of an attachment of tubularseal 130 to the expandable member 110 while also allowing for improvedload transfer to the expandable member 110. In some cases, the crossstitches secure tubular seal 130 at intersections 118 locatedimmediately above (proximal) the inflow crowns 115. Cross stitches 132can be formed by passing two stitches 132 a, 132 b of a suture inorthogonal directions over the intersections 118 and through the tubularseal 130. In some cases, preformed apertures 131 for cross stitch 132can be formed in the tubular seal 130. In some cases, a portion of thetubular seal 130 that is sutured by cross stitch 132 includes aninternal fabric, such as those discussed below. Each cross stitch 132can be knotted independently. As shown in FIG. 5C, cross stitches 132each include a separate knot 137. Additionally, cross stitches 132 canbe arranged to not pass through leaflets 200. Cross stitches 132 can berepeated at a plurality of intersections 118 (FIG. 5A) circumferentiallyaround an inflow end of a prosthetic heart valve provided herein suchthat an entire circumference of tubular seal 130 is securely attached.In some cases, each intersection 118 immediately adjacent to inflowcrowns 115 is sutured to tubular seal 130 via a cross stitch providedherein. The tubular seal stitching pattern provided herein can increasethe strength of the attachment between the tubular seal 130 and theexpandable member 110 while also allowing for improved load transfer tothe expandable member 110 through the use of the plurality of crossstitches.

Tubular seal 130 can have any suitable structure. In some cases, tubularseal 130 can include an elastic material. In some cases, tubular seal130 can include one or more layers of an elastomeric polymer. In somecases, tubular seal 130 can include a polycarbonate, polyurethane,silicone, polytetrafluoroethylene (PTFE), or a combination thereof.Other suitable materials include, but are not limited to, natural andsynthetic rubbers, including cis-1,4-polyisoprene rubber,styrene/butadierie copolymers, polybutadiene rubber,styrene/isoprene/butadiene rubber, butyl rubber, halobutyl rubber;polyurethane elastomers, including elastomers based on both aromatic andaliphatic isocyanates; flexible polyolefins, including flexiblepolyethylene and polypropylene homopolymers and copolymers; styrenicthermoplastic elastomers; polyamide elastomers; polyamide-etherelastomers; ester-ether or ester-ester elastomers; flexible ionomers;thermoplastic vulcanizates; flexible poly(vinyl chloride) homopolymersand copolymers; flexible acrylic polymers; and blends and alloys ofthese, such as poly(vinyl chloride) alloys like poly(vinylchloride)-polyurethane alloys. In some cases, tubular seal 130 caninclude an aliphatic polycarbonate-based thermoplastic urethane. In somecases, tubular seal 130 can include an elastomeric polymer having ahardness ranging from 3.07 MPa to 9.9 MPa, or a durometer ranging from75 Shore A to 75 Shore D using ASTM standard D2240 in force on Jan. 1,2014. In some cases, tubular seal 130 can include a polymeric materialhaving the mechanical properties shown in Table I below. Notably, all ofthe listed ASTM standards refers to the standard in force on Jan. 1,2014.

TABLE I ASTM Standard Durometer Range Available 75 Shore A-75 Shore DD2240 Specific Gravity 1.10-1.14 D792 Melt Flow 2-26 g/10 min(205°C./3.26 kg) D1238 MECHANICAL PROPERTY RANGES ASTM Standard Durometer75A-B20 55D 75D 75D Ultimate Tensile Strength (psi)  400-9000 5000-10000 3000-8000 D638 Tensile (psi) @50% elongation 350-6501500-1800 3000-8000 D638 @100% elongation 550-850 1800-2200 3000-8000D638 @200% elongation  600-1200 2800-4200 D638 @300% elongation1200-2000  4200-10000 D630 Ultimate Elongation (%) 350-750 200-400100-300 D638

In some cases, referring back to FIG. 1A, tubular seal 130 can includeattachment structures to improve the attachment of the tubular seal 130to leaflets 200 and/or expandable member 110.

In some cases, as shown in FIG. 7A, a tubular seal 730 can include aninflow end section 740 and an outflow end section 750. The inflow endsection 740 can include a fabric embedded within elastomeric materialand the outflow end section 750 can include a plurality of grommets 732.The fabric of inflow end section 740 can be a woven material. In somecases, the fabric can have warp threads and/or weft threads. The fabricis composed of fibers having an average thread diameter from about0.00002 inches to about 0.002 inches (or from about 0.5 microns to about50 microns), more preferably from about 0.0008 inches to about 0.002inches (or from about 20 micron to about 40 microns). In some cases,more preferably, the fabric is composed of fibers having a threaddiameter of about 0.0011 inches (about 27 microns).

In some cases, the fabric can include non-elastomeric fibers. Suitablenon-elastomeric fiber materials include, but are not limited to,polyolefins, polyesters such as PES 38/31 manufactured by SaatiTech, andpolyamides. More particularly, the polyolefins may be, for example, oneor more of polyethylene, polypropylene, polybutene, ethylene copolymers,propylene copolymers, and butene copolymers. Because the fabric caninclude non-elastic fibers, inflow end section 740 and outflow endsection 750 can have different overall elastic properties. In somecases, tubular seal 730 can be used as a tubular seal 130 of prostheticheart valve 100, as previously shown in FIG. 1A. In some cases, tubularseal 730 can be used in other prosthetic heart valves provided herein.

As shown in FIGS. 7A-7D, an interface 753 between the inflow end section740 and the outflow end section 750 is non-linear due to a non-linearedge of fabric within the inflow end section 740. As shown in FIG. 7A,the non-linear edge can be sinusoidal 753. In some cases, as shown inFIGS. 7C-7D, the non-linear edge can be a zigzagged edge 754, a steppededge 755, or a scalloped edge 756.

In some cases, inflow end section 740 can be thicker than outflow endsection because of the presence of a fabric within inflow end section740, 750. In some cases, inflow end section 740 can have a thickness ofabout 0.0028 inches (about 70 microns) and the outflow end section 750can have a thickness of about 0.0020 inches (about 50 microns). Othersuitable thicknesses for the inflow end section include thicknessesranging from about 0.0020 inches to about 0.0035 inches (about 50microns to about 90 microns), or more preferably, from about 0.0025inches to about 0.0031 inches (about 60 microns to about 80 microns).Suitable thicknesses for the outflow end section include thicknessesranging from about 0.0011 inches to about 0.0028 inches (about 30microns to about 70 microns), or more preferably, from about 0.0016inches to about 0.0023 inches (about 40 microns to about 60 microns). Insome cases, suitable thickness ratios of the inflow end section relativeto the outflow end section can range from 1:1 to 1.2:1, from 1.2:1 to1.4:1, from 1.4:1 to 1.5:1, and from 1.5:1 to 2:1. A non-linear edge canproviding a non-linear interface between the inflow end section 740 andthe outflow end section 750. A prosthetic heart valve with thenon-linear interface may have an increased overall diameter that tapersmore gradually when compared to a prosthetic heart valve that has alinear interface. The non-linear edge of the fabric can also graduallytransition the change in elastic properties between the outflow endsection 750 and the inflow end section 740, mitigating the formation ofstress concentrators along the interface 753 that can cause tearing inthe tubular member. Additionally, the shape of non-linear interface 753can limit the propagation of tears.

In some cases, the fabric can be arranged in the inflow end section 740to allow for the fabric within inflow end section 740 to stretch inaxial and/or radial directions to allow the tubular seal to stretchalong with an expandable member during implantation. When the fabricdoes not allow the tubular seal to adequately stretch, the seal cancause non-uniform crimping during manufacturing or damage the expandablemember during device deployment. In some cases, a woven fabric can bearranged to have the warp and the waft extend in directions oblique tothe axis of the tubular seal. This can allow the fabric to flex inradial and/or axial directions relative to the axis of the tubular seal,but limit the fabric from stretching in a direction oblique to the axis.In some cases, both the warp and the waft can extend at an angle between30 degrees and 60 degrees with the axis of the tubular seal. In somecases, both the warp and the waft can extend at an angle between 5degrees and 70 degrees with the axis of the tubular seal. In some cases,the warp and waft can be arranged within the tubular member 730 to forman angle of about 45 degrees with the axis of the tubular seal. In somecases, the fabric can be a knit fabric arranged to allow for apredetermined amount of stretch in the axial and/or radial directions.Limiting the fabric within inflow end section 740 from stretching in adirection oblique to the axis can prevent the fabric from bunching andminimize non-uniform crimping during manufacturing.

Additional exemplary tubular seals including a fabric and grommets aredescribed in U.S. Patent Application No. 2013/0090729, which is herebyincorporated by reference in its entirety. For example, U.S. Pat. No.8,778,020 describes a seal that includes a multilayer, cylindrical sealbody having projections alternating with recesses along the proximaledge of the seal body with proximal reinforcing grommets and a distalreinforcing band, which may be formed from a woven or nonwoven fabricand either incorporated within the interior of the multilayer seal bodyor adhered to the surface thereof.

In some cases, tubular seals described in U.S. Patent Application No.2013/0090729 can be modified to include a fabric arrangement that allowsa seal to stretch in axial and/or radial directions. In some cases,elastomeric materials provided herein can be incorporated into thetubular seals disclosed in U.S. Patent Application No. 2013/0090729. Insome cases, the tubular seals described in U.S. Patent Application No.2013/0090729 can be modified to include the non-linear interface 753provided herein.

Referring back to FIG. 7A, tubular seal 730 can be created by producingone or more layers of elastomeric polymer, applying the fabric andgrommets 732 to the one or more layers of elastomeric polymer, andovercoating the fabric and grommets 732 with one or more additionallayers of elastomeric material. In some cases, different layers can havedifferent elastomeric properties. In some cases, tubular seals (e.g.,130, 730, or 760) can include a radially innermost layer including atleast one elastomeric polymer, e.g., a polycarbonate and a polyurethane;a radially outermost layer including at least one elastomeric polymer,e.g., a polycarbonate and a polyurethane; and at least one inner layerdisposed between the radially outermost layer and a radially innermostlayer. In some cases, the modulus of elasticity of the innermost layeris less than the modulus of elasticity of the radially innermost outerlayer and the modulus of elasticity of the radially outermost outerlayer. In some cases, the elongation to break of the inner layer isgreater than the elongation to break of the radially innermost outerlayer and the elongation to break of the radially outermost outer layer.Although the radially innermost outer layer and the radially outermostouter layer have been depicted as including the same material, it willbe appreciated that they may be compositionally the same or different.

The multilayer tubular seals provided herein (e.g., 130, 730, 760) maybe formed in a variety of ways. In some cases, multilayer tubular sealsprovided herein may be formed by successive applications of a polymersolution to an appropriately shaped mandrel, such as that illustrated inFIG. 6. Following a careful cleaning of the mandrel 600, the mandrel maybe mounted to an appropriate holding fixture in a spray booth. A firstcoating composition including a carrier and at least one polymer may beapplied to the mandrel 600 and subsequently dried to form a first coatedmandrel. In some cases, the first coating composition includes one ormore elastomeric polymers, e.g, polycarbonate and/or a polyurethane, anda volatile carrier. The coating composition may be applied as a singlelayer or multiple layers to achieve the desired dried coating thickness.The grommets 732 (FIG. 7A) and the fabric may be positioned on the firstcoated mandrel by inserting locating pins 620 in apertures 610 in thetapered mandrel 600 which align with corresponding perforations 30provided in the grommets 32, 34, 36 and the fabric 40. In FIG. 6, onlyone pin 620 has been illustrated for clarity. In some instances, it maybe desirable to secure the plurality of grommets 732 and the fabric tothe mandrel or to an underlying coating layer by applying a drop of afirst coating composition, or other adhesive composition, to each itemto ensure that it remains properly positioned during subsequentprocessing. The fabric can be cut to a suitable shape having anon-linear edge using any suitable method. In some cases, the fabric canbe die cut. In some cases, the fabric can be cut with a blade. In somecases, the fabric can be cut using a femtosecond laser. In some cases, afemtosecond laser cut fabric mitigate the chances of forming stressconcentrators along the edge of the fabric.

A second coating composition including a carrier and at least onepolymer may be applied to the first coated mandrel, the fabric, and theplurality of grommets. In some cases, the second coating compositionincludes one or more elastomeric polymers, e.g, polycarbonate and/or apolyurethane, and a volatile carrier. The carrier of the second coatingcomposition may be removed, thereby forming a second coated mandrel. Thesecond coating composition may be applied as a single layer or asmultiple layers to achieve the desired dried coating thickness. In somecases, the second coating composition may be different from the firstcoating composition. In some cases, the second coating composition maybe composed of the same material as the first coating composition.

In some cases, a third coating composition including a carrier and atleast one polymer may be applied to the second coated mandrel. In somecases, the third coating composition includes one or more elastomericpolymers, e.g, polycarbonate and/or a polyurethane, and a volatilecarrier. The carrier of the third coating composition may be removedthereby forming a tubular seal precursor. The third coating compositionmay be applied as a single layer or as multiple layers to achieve thedesired dried coating thickness. In some cases, the third coatingcomposition may be different from the first coating composition. In somecases, the third coating composition may be the same as the firstcoating composition. In some cases, the third coating composition may bedifferent from the second coating composition. In some cases, the thirdcoating composition may be the same as the second coating composition.Following removal of the carrier from the third coating composition, thetubular seal precursor may be inspected to ensure that it is fullyformed and meets dimensional specifications, such as a thicknessspecification. In some cases, a suitable thickness for the tubular sealprecursor can range from about 0.001 inches to about 0.0030 inches(about 30 microns to about 75 microns) or from about 0.002 inches toabout 0.0047 inches (about 50 microns to about 120 microns). Othersuitable thicknesses for the tubular seal precursor include a range fromabout 0.0008 inches to about 0.002 inches (about 20 microns to about 40microns), about 0.001 inches to about 0.002 inches (about 30 microns toabout 50 microns), about 0.002 inches to about 0.0029 inches (about 50microns to about 75 microns), about 0.002 inches to about 0.004 inches(about 50 microns to about 100 microns), about 0.004 inches to about0.0047 inches (about 100 microns to about 120 microns), about 0.004inches to about 0.0059 inches (about 100 microns to about 150 microns),about 0.0059 inches to about 0.0079 inches (about 150 microns to about200 microns), as well as any thickness value within any of the listedranges.

In some cases, the tubular seal precursor may be inspected to ensurethat it meets certain functional specifications, e.g., tensile andfrictional specifications. The tubular seal precursor may then betrimmed by laser cutting, or blade cutting, to conform to dimensionalspecifications and removed from the tapered seal-forming mandrel as aformed tubular seal. In some cases, at least some preformed aperturesfor suturing tubular seal to expandable member 110 and/or leaflets 200can be performed by laser cutting. In some cases, at least some of thegrommets may be formed by a laser cutting operation performed on atubular seal precursor. In some cases, grommets 732 of FIG. 7A may beadded to the multilayer, generally cylindrical seal, in a step notillustrated, as a proximal band. Subsequent laser cutting of the tubularseal precursor would then simultaneously form grommets 732 by removingthe portions of the proximal band located between the projections.

In some cases, coating compositions may be selected to provide arelatively stiff dried polymer such as a dried polymer having a Shore Dhardness of about 55, or a hardness of about 6.21 Megapascals (Mpa). Insome cases, coating compositions may be selected to provide a relativelyelastomeric dried polymer such as a dried polymer having a Shore Ahardness of about 80, or a hardness of about 3.45 MPa. In some cases,the first and third dried polymer layers may have a Shore D hardness of55, or a hardness of 6.21 MPa, and the second layer may have a Shore Ahardness of 80, or a hardness of 3.45 MPa.

Although in some cases described above, three polymer layers wereemployed, it will be appreciated that a greater or lesser number oflayers may be employed and that each of the three or more layers mayinclude two or more sublayers. In some cases, the plurality of grommetsand the fabric can be positioned between the first and second coatinglayers. In some cases, the plurality of grommets and the fabric can bepositioned elsewhere within the tubular seal, e.g., within a layer, oron the radially innermost or radially outermost surface of the tubularseal.

The mandrel 600 of FIG. 6 includes a taper which results in a tubularseal having a slightly smaller diameter proximal end compared to thediameter of the distal end. In some cases, the diameter of the proximalend can include a diameter reduction of about 3% to about 30% ascompared to the diameter of the distal end. The taper allows the tubularseal to be removed from the mandrel with relative ease upon completionof the fabrication process. The smaller proximal diameter of the tubularseal tends to cause the proximal projections to lie more firmly againstan anchor element of the replacement heart valve. In some cases, thesurface of the mandrel may be textured to create a tubular seal with areduced contact area. In some cases, the mandrel can be textured using abead blasting process. In combination with the selection of a relativelyhard outer layer, a textured seal surface is believed to result in alower friction surface.

As shown in FIG. 7E, a tubular seal 760 can include a woven or non-wovenfabric embedded throughout a polymer or metal matrix structure. In somecases, at least one leaflet of the heart valve can be secured to thetubular seal in a portion of the tubular seal including the woven ornon-woven fabric to minimize blood leakage between the tubular seal andthe leaflets.

In some cases, the matrix structure can be made of elastomeric material.In some cases, tubular seal 760 can be made of the fabric alone. Thefabric can include non-elastic fibers arranged to allow for the tubularseal 760 to stretch in axial and/or radial directions relative to theaxis of the tubular seal 760. In some cases, the non-elastic fibers canbe arranged within the tubular member 760 to form an angle of about 45degrees with the axis of the tubular seal. In some cases, the fabric canbe a knit fabric arranged to allow for a predetermined amount of stretchin the axial and/or radial directions. In some cases, the fabric can bemade of polymeric materials that include, but are not limited to,polyesters, polyolefins such as polyethylene and polypropylene,polyamides, nylons, and combinations thereof. In some cases, the fabriccan have a thickness ranging from about 0.002 inches to about 0.003inches (about 40 to about 80 microns). In some cases, the fabric can bewoven such that spacings between individual fibers create openings inthe fabric that together constitutes from about 20% to about 40% of afabric surface.

A number of embodiments of the invention have been described.Nevertheless, it will be understood that various modifications may bemade without departing from the spirit and scope of the invention.Accordingly, other embodiments are within the scope of the followingclaims.

What is claimed is:
 1. A prosthetic heart valve comprising: anexpandable member comprising one or more braided wires, the one or morebraided wires comprising a first set of wire segments extended helicallyin a first direction and a second set of wire segments extendedhelically in a second direction such that each wire segment of the firstset intersects a plurality of wire segments from the second set at aplurality of intersection points, wherein the one or more braided wireshave crowns where the wire segments of the first set connect to wiresegments of the second set; a plurality of leaflets being secured withinthe expandable member; and a tubular seal comprising an elastomericmaterial, the tubular seal having an inflow edge being secured to bottominflow edges of the plurality of leaflets and to the expandable memberby a plurality of sutures, characterized by the sutures comprising crossstitches formed around both a wire segment of the first set and a wiresegment of the second set at one of the intersection points.
 2. Theprosthetic heart valve of claim 1, wherein each cross stitch is anindependently tied off stitch unconnected to other cross stitches. 3.The prosthetic heart valve of claim 1, wherein each cross stitch isattached at an intersection point immediately adjacent a crown at aninflow side of the expandable member.
 4. The prosthetic heart valve ofclaim 1, wherein the plurality of leaflets are secured together alongside edges thereof.
 5. The prosthetic heart valve of claim 4, whereinthe plurality of leaflets each comprise two sleeve portions, wherein thesleeve portions are secured to the expandable member by a plurality ofanchor elements.
 6. The prosthetic heart valve of claim 1, wherein thetubular seal comprises a plurality of non-elastic fibers retained withina matrix of the elastomeric material, the non-elastic fibers beingarranged to allow the tubular seal to stretch in an axial or a radialdirection.
 7. The prosthetic heart valve of claim 6, wherein thenon-elastic fibers are part of a fabric.
 8. The prosthetic heart valveof claim 7, wherein the fabric has a thickness ranging from about 40 toabout 80 microns.
 9. The prosthetic heart valve of claim 7, wherein thefabric is a woven fabric.
 10. The prosthetic heart valve of claim 9,wherein the woven fabric comprises fibers in a warp direction and fibersin a waft direction, wherein the fibers in both the warp direction andthe waft direction are angled with respect to a central axis of thetubular seal.
 11. The prosthetic heart valve of claim 10, wherein thefibers in both the warp direction and the waft direct are angled at anangle between 5 degrees and 70 degrees with respect to the central axisof the tubular seal.
 12. The prosthetic heart valve of claim 7, whereinthe fibers are made of polyester.
 13. The prosthetic heart valve ofclaim 6, wherein the non-elastic fibers are uniformly dispersedthroughout the matrix.
 14. The prosthetic heart valve of claim 1,wherein the tubular seal has a substantially uniform thickness.
 15. Aprosthetic heart valve comprising: an expandable member comprising oneor more braided wires, the one or more braided wires comprising a firstset of wire segments and a second set of wire segments such that eachwire segment of the first set intersects a plurality of wire segmentsfrom the second set at a plurality of intersection points; a pluralityof leaflets being secured within the expandable member; and a tubularseal comprising an elastomeric material, the tubular seal having aninflow edge being secured to bottom inflow edges of the plurality ofleaflets and to the expandable member by a plurality of sutures, whereinthe sutures comprise cross stitches formed around both a wire segment ofthe first set and a wire segment of the second set at one of theintersection points; wherein the tubular seal comprises an outflow endregion and an inflow end region, the inflow end region being a portionof the tubular seal comprising a fabric within a matrix of anelastomeric matrix, wherein the fabric has a non-linear edge defining aninterface between the inflow end region and the outflow end region. 16.The prosthetic heart valve of claim 15, wherein the non-linear edge ofthe fabric has a sinusoidal or scalloped shape.
 17. The prosthetic heartvalve of claim 15, wherein the plurality of leaflets are secured to thetubular seal by a continuous circumferential running stitch.
 18. Theprosthetic heart valve of claim 15, wherein the first set of wiresegments extends helically in a first direction and a second set of wiresegments extends helically in a second direction.
 19. The prostheticheart valve of claim 18, wherein the one or more braided wires havecrowns where the wire segments of the first set connect to wire segmentsof the second set.
 20. A method of making a tubular seal of a prostheticheart valve, the method comprising: forming a tubular seal that includesa fabric within a matrix by dipping a mandrel with a first coatingcomposition comprising at least one elastomeric polymer; drying thefirst coating composition; positioning the fabric on the mandrel;applying a second coating composition on the mandrel, the second coatingcomposition being different than the first coating composition; andremoving the tubular seal from the mandrel.